The Welding Gear (page 2)
Previous page: Stick and MIG Welding
Welding Helmet
As mentioned already, the electric spark and the welding arc that follows emit blindingly bright light. If your eyes catch just a momentary glimpse of it, you will immediately know how painful that
experience can be. Any longer exposure can be detrimental to your vision. In addition to the light, the welding arc radiates strong UV (ultra-violet; high frequency) and IR (infra-red; heat, low frequency)
rays that would not only give any exposed skin a quick sun-tan, but represent a long term health hazard.
A welding helmet protects your eyes, whole head and neck, and gives you the possibility to actually see what you are doing. Apart from an ergonomic design, lightness and comfort to wear, the most important
part is the see-through filter lens. The picture to the right shows two different helmet types:
- The helmet on the right is the most basic (and the cheapest) one, with a flip-up dark filter (different dark shades are available) lens, a clear glass protective lens underneath that may be used when grinding or
flipped up to leave an unprotected rectangular opening. The problem with these cheap basic models is that the dark filter lens is selected to protect your eyes while the bright welding arc is on, but before
or after that you see absolutely nothing but darkness (unless you use very bright lights on the welding area, and even then it might be hard to see much). That means that you have to get the welding gun
(and yourself) in position almost touching the material to be welded, than lower the helmet with the other hand (the experienced welders have their helmets adjusted loosely, so they drop the helmet
down into the working position with just a quick nod of their head), touch the material with the electrode to start the arc and start seeing again. It takes a great experience to practice this
blind start so much that the beginning of the weld is acceptable without corrections. Helmets like this are mostly used for stick welding where high starting precision is not critical.
- The helmet to the left is a top of the range auto-darkening filter lens model. Its main quality is that you always see through the lens, even before you start the welding arc, so you can confidently
guide your hand with the welding gun. The moment you light the arc, the auto-darkening feature of the lens senses the transition and darkens the filter to protect your eyes. With quality contemporary
filter lenses this switching time is 1/25000 sec (0.04 msec) or better, which is really fast and good for your eyes.
Buy a good quality, fast auto-darkening helmet. It is your eyesight you are protecting. Welding a boat hull together is not a comfortable job. You often weld in tight corners and in uncomfortable positions, sparks of molten metal fly around, your work
generates intense heat and fumes you should avoid breathing. Get yourself a good helmet, it is one of the best things you can do to improve your effectiveness, your working comfort and the quality of
your weld.
I have seen a man using a low-cost stick welder to fix an old car, welding without a helmet and without gloves. He would just come close with the stick-electrode, shut his eyes and
touch the sheet metal for a split of a second, move the hand away, open his eyes to check the result, and repeat the process again and again. Spot welding of a sort. He was doing a professional job,
in a very unprofessional way. Most probably he was unaware of the consequences. Don't do foolish things like this.
But then, you should buy two helmets. Welding is far more effective if the welder has an assistant. She/he could often hold things together for that first material positioning tack-weld, flip the fan
on to blow the fumes away the moment the welding stops, pass the things that the welder crouching in the bilges of the hull needs, hold the gun while you quickly take the gloves off to cool your
fingers that almost got welded to the metal piece you were working on, hold the light to help you see better before you start the arc, adjust the welding voltage on the base welder unit as you requested,
keep a good company and do countless small jobs that make your work easier. And your assistant, often as close to the welding arc as you, needs the same type of protection as you do, helmet and gloves
included. If the budget permits, buy the second auto-darkening helmet. But even that cheap dark-glass one will do.
Sunglasses and blowtorch goggles do not provide adequate protection for welding.
More Welding Gear and Other Basic Tools
The tools on the picture to the right are numerated:
(click on the blue text to shrink/expand)
- The ground electrode of our MIG welder.
It consists of a thick electrical cable ending in a metal clamp. You attach the clamp to the material you wish to weld so
that both pieces you will weld have a very good ground contact.
- The MIG gun of our welder.
When you press the red button, both the shielding gas (argon in case of aluminum) and the welding wire start flowing from the tip.
The wire itself is the other electrode. As it touches the materials to be welded, it starts the electric arc and melts into the welding pool. New wire keeps coming and melting into the pool, together
with some of the material being welded melting under the heat.
How deep is the melting of the base materials depends on the welding settings, primarily on the strength of the electric current. It is called penetration, and it must be sufficient to
ensure a strong bond of the two pieces. If it is not enough, the weld is cold and weak. If it is too deep, the weld is too hot and loses in strength, with the risk of burning a hole
through. When you build up your welding experience, you will be able to tell if the weld is too cold, just right or too hot.
- MIG gun tips.
When you look at picture of the MIG gun, that silvery cylinder at the end is the nozzle. Pull it straight off, and you will
expose underneath the copper tip and the holes through
which the shielding gas (argon in case of welding aluminum) flows out. The diameter of the tip opening, etched on its side, has to match the diameter of the filler wire used. You unscrew the tip off
to exchange it or to clean it using that simple key shown under 5.
- Special MIG welding wire cutters (used also to clean the MIG gun nozzle).
The welding wire comes out of the tip and sticks out at the centre of the nozzle (without touching it, so the nozzle is
electrically isolated). When you end a weld, a tiny ball forms on the wire. You need to cut it off before almost every start of a new weld, as it may otherwise cause an improper (delayed) start
of the arc and lots of sparks. If the wire does not already stick out of the nozzle, depress the gun trigger for a brief moment, then cut the wire with these cutters flash with the nozzle
opening. The two pins that stick out in front of the cutters (see the picture) are dimensioned to fit exactly inside the nozzle to clean the sediments out without taking the nozzle off.
Welding likes cleanliness; you will need to do this cleaning whenever you notice that too much dirt has collected inside the nozzle.
- Key to loosen/tighten the MIG gun tip.
To use it, take the nozzle off, put this simple tool over the tip and turn to unscrew or tighten. You need to take the tip off
to change it when you change the filler wire, or here and there, not so often if your welding setting are OK, if the wire gets stuck within the tip. If the tip openning needs cleaning, you need
to take it off and use a proper dimension manual "drill" bit (you buy these bits as a low-cost set for different tip diameters).
- Kitchen scourer (Scotch-Brite or similar), for final fine cleaning of the surface
before welding.
I can't remember where we picked this one up, but the regular kitchen scourer is excellent for this final cleaning job, especially when you weld aluminum.
You can clean the area to be welded with the stainless brush (number 7) first, and then for the extra clean touch use this scourer. The picture shows two pads, a green and a red one, yet color is really not important.
- Stainless steel brush (when new, it looks like a stainless steel looks; these have been heavily used).
For welding aluminum, it is essential you use only stainless steel brushes, never ordinary steel ones, as they would
contaminate the weld zone with steel impurities that would weaken the weld. Plus, every brush shads its "hair" during its hard working life. Remember electrolysis as aluminum's worst enemy? The stainless
steel is the closest with aluminum and the only other metal that should some in contact with your aluminum hull. And even stainless steel you use only where you must, for extra strength. Any other metal,
including regular steel brush bits that may find their way into the bilges and stay there, means asking for trouble.
- Heavy leather welding gloves.
They are heavy and awkward. But you don't need precise finger action when you weld with a stick or MIG welder (for TIG welding, described
later, you use light gloves that give you much better precision). But you do need all
protection from the harsh welding conditions you can get. Just have a look at the gloves on the picture. It is obvious they have been through some tough times. Sometimes your fingers will feel like
burning inside, as you press to finish that last inch of the weld.
- Files, files, files.
Occasionally you will need to do some filing. As an example, preparing the edges of two aluminum (or steel) plates for welding
requires cleaning them. Using first the file on the edge itself, then a stainless steel brush (for aluminum; if you are working with steel, ordinary steel brushes are fine) to clean about 10-15 mm
(about 1/2 inch), and finishing with a scourer pad, you will take off the oxide and dirt from the surface of the (aluminum) plate. Your files should be of the coarse type, doing a faster job, and
one-two finer ones. As a minimum, you need a bigger size flat coarse file, and one half-round finer one. Again, if welding aluminum, be extra careful not to file steel and then aluminum with the
same file(s), as that would contaminate the aluminum, especially the welding zone. Keep disparate metals strictly apart.
- Light rubber mallet.
Here and there you will need to gently thump something into place. A choice of rubber mallets of different sizes will make
your life easier.
- Heavier rubber mallet ("The Gentle Persuader").
One bigger rubber mallet (we named it "The Gentle Persuader") will be able to do the job where a heavier thump is required.